Unlike the mess Brexit has left the UK in, Americans should be glad that their constitution actually works – especially in the age of Trump

The level of uncertainty facing the UK would be unlikely in most constitutional democracies. And much of this stems from the introduction of a referendum into a system that can only tolerate such a mechanism if it reaffirms the status quo

Theresa May is experiencing the flaws in our unwritten constitution (EPA)

Among liberal Americans there is a common lament. After two centuries and more of venerable service, their constitution is struggling to cope with an instinctive autocrat such as Donald Trump. Its celebrated checks and balances are failing; its constraints are too weak to stop someone so set on smashing the machine.

In fact, it seems to me, the US constitution has stood up pretty well to the challenges of this aberrant president. If anyone’s constitution is in trouble today, it’s less theirs than ours, as it tries and fails to resolve the conundrum set in train by Brexit.

As the parliamentary debates wend their way towards next week’s crucial votes, what we are watching is the showdown – inevitable since the result of the EU referendum – between the claims of a popular vote and a supposedly “sovereign” parliament. If the two are at odds – and they are – which takes precedence? It is no accident opponents of Brexit – and it is mostly them hoping for another outcome – are calling not for a second referendum, but for a “people’s vote”, which would thus have equal, and they hope opposite, force to the vote of 2016.

A House of Commons vote will not command that like-for-like authority, and that is one reason so many MPs find themselves conflicted between voting according to the known will of their constituents and their own judgement. Their constitutional status as “representatives”, rather than “delegates”, means, in theory, they should vote according to their own lights. That is what they could have done if there had been no referendum. But now? The people spoke and MPs – on balance and with heavy heart, many of them – feel a democratic duty to follow.

The difficulty is that our constitution does not know what to do with a referendum, at least not one that goes the “wrong” way. It is a different animal; an intrusion. And this highlights a bigger problem.

For a long time, we British – or maybe English? – fancied our unwritten constitution was superior to other varieties. It was not for us to be chained to the letter of a basic law whose every dot and comma required ponderous procedures before it could be adapted to changing times. Our arrangements were capacious, flexible and eminently practical: an expression of our can-do, muddle-through country at its best.

Except certain changes – especially some relatively recent changes – have left us with a shambles of competing powers and no ultimate arbiter to sort it all out. The creation of the Supreme Court went some way towards a US-style separation of powers but also compromised the sovereignty of parliament. Devolution may have been positive in many ways for Scotland, Wales and Northern Ireland, but constitutionally it has been a mess. Unlike in an ordered federal system, such as those of the US or Germany, the devolved powers are different for each territory and are still subject to change – for instance in the tax-levying power of Scotland – and even, as occurred recently in Northern Ireland, suspension.

The “wrong” result in the EU referendum has produced a potential stand-off between parliament and people and there is no rulebook for what to do next. It is not just that the prime minister and/or government could fall as a consequence of next week’s vote – such is the price of democracy. It is rather that, with both major parties divided and the country similarly split, the only way the referendum result can realistically be honoured is by a compromise along the lines set out by the prime minister. Yet compromise looks further away than ever.

The standoff is such that within days the UK could be facing any or all of the following: an orderly “soft” Brexit achieved by the narrowest of majorities – or none; a Conservative leadership contest – and possible split of the party; a new referendum – “people’s vote”; and a general election. Such a level of uncertainty would be unlikely in most constitutional democracies. And much of this stems from the introduction of a referendum into a system that can only tolerate such a mechanism if it reaffirms the status quo.

It has taken a shrewd parliamentarian and lawyer, Dominic Grieve, to attempt a rescue. His amendment gives MPs the chance to find an alternative to the UK simply crashing out of the EU if members vote down the prime minister’s deal. Grieve’s solution has, in the view of some, returned “sovereignty” to parliament. Whether “the people” will consent to that remains to be seen. That is the difficulty caused by holding a referendum.

All of which goes to explain why, even with the challenges posed by Trump, it seems to me the US constitution is in rather better shape. For all his impetuosity, Trump has been held in check. His intention to impose special curbs on the admission of, mostly Muslim, migrants and refugees was limited by the courts, with voluntary organisations and others mounting spontaneous popular support. Any hopes this unlikely president might have had of downgrading the US commitment to its European allies or upgrading relations with Russia have been thwarted by congress. Trump’s latest Supreme Court nominee, Brett Kavanaugh, was subjected to a combative Senate hearing then approved – just – by the requisite majority. This is how these things are supposed to be done.

In the midterm congressional elections, the Republicans lost control of the House of Representatives, but marginally increased their majority in the Senate. That could make life for Trump more difficult – Democrats will control House committees and wield subpoena power – but slightly easier in other respects, for instance around judicial appointments. That seems a fair reflection of the contradictory will of the people in relation to Trump, and of how US democratic practice and the constitution successfully coincide.

Of course, there are defects. Hillary Clinton might reasonably challenge the whole principle of the electoral college. But in what might be seen as the two biggest crises of the last 30 years – the impeachment of Bill Clinton and the tied election of 2000 – we reporters carried copies of the constitution around with us to find out at each stage what should happen next, and the precepts laid down in 1787 held up remarkably well.

The problems with US democracy are less constitutional than practical: gerrymandered constituencies, obstacles to poor and minority voters exercising their rights, voting machines too primitive to produce an accurate recount, and – in first place – the corrupting power of big money.

Overall, though, the durability of the US constitution and the political chaos we face over Brexit today make for an instructive contrast. If and when our relations with the EU are finally resolved, might we not take another look at the supposed merits of our unwritten constitution? After all, the vast political energy spent on the Brexit fracas will need somewhere to go and if recent overheard conversations are any gauge, the appetite for history and the law is newly alive.

Bus passengers who can cite the Corn Laws and even the English civil war as proof of an age-old divide will surely flock to join another, perhaps less anguished, national debate.